Field of the Invention
[0001] This invention pertains to film-enrobed unitary-core products such as medicine tablets,
to films and film compositions for making such products, and to methods and equipment
for manufacturing such products. More specifically, it pertains to medicines and the
like comprising cores of one-piece tablet nature in various shapes which are enrobed
in digestible or erodable films applied after formation of the cores. It also pertains
to gelatin-based and other films for enrobing such cores, to methods for enrobing
such cores with such films, and to equipment for performing such methods to produce
such products.
Background of the Invention
[0002] It is known to dip or spray tablet-type medicine dosage units with gelatin or other
materials to make them more palatable, easier to swallow, less prone to powder or
to flake when handled in bottles, colored for eye appeal or identifiability, and longer
lasting before active ingredients degrade, among other reasons. Capsule forms of such
products occur as soft gelatin capsules, which commonly are of spherical or oblate
spherical shape, and as hard gelatin capsules which commonly are of elongated round-ended
cylindrical form and which are made in two pieces for assembly, with or without sealing,
around the flowable fill material containing the desired active ingredients.
[0003] The portion of U.S. Patent 4,820,524 entitled "Background of the Invention" (which
portion is incorporated herein by reference) presents a comprehensive review of hard
gelatin encapsulated medicines and the like, and of certain forms of solid medicaments
having spray-applied or dip-applied gelatin coatings. Because of the problem of tampering
which had been experienced with hard gelatin capsule products, many manufacturers
of such products withdrew them from the market in favor of other forms of active-ingredient
presentment, notably caplets. The withdrawal of hard gelatin encapsulated products
from the market left those manufacturers with idle machines for making hard gelatin
capsules, a situation which Patent 4,820,524 addressed by its descriptions of how
such machinery could be modified to produce an at least twice-dipped, gelatin-coated
caplet form of medicine. The resulting final product can be colored uniformly, or
it can be colored differently at its opposite ends by differently tinting the gelatin
baths into which each of the opposite ends of the caplet preform is dipped at least
once. A number of advantages of such products over hollow hard gelatin capsules and
over pan-coated tablets are noted in Patent 4,820,524 at column 11, lines 19 et seq.
[0004] In its detailed description, namely, at column 10, lines 47 et seq., Patent 4,820,524
notes that the dipping of preformed caplets into wet gelatin baths can have disadvantageous
effects, and that precoating of the caplet with a sealant, such as a moisture barrier,
can be useful.
[0005] While the procedures described in Patent 4,820,524 for producing at least twice-dipped,
gelatin-coated caplets are relatively simple, the machinery required for high-volume
implementation of those procedures is quite complex, extensive and expensive. Also,
those procedures and that machinery are not well suited for handling solid medicament
preforms in shapes other than caplet shape.
[0006] U.S. Patents 2,663,128 (1953), 2,697,317 (1954), and 2,775,080 (1956), all issued
to F.E. Stirin and A.S. Taylor as assignors to American Cyanamid Company, describe
complex procedures and equipment in which a suitable active ingredient powder is formed
into a soft pellet. The pellet is transferred into a cup-like depression formed by
vacuum in a plastic gelatin film. The cup-like depression can also contain a liquid.
The film which defines the loaded depression is moved into contact with a second gelatin
film which is sealed across the depression. The loaded and sealed depression is cut
from the adhered pair of films, and the product then self-adjusts its shape to a desired
tablet, sphere, or capsule-like shape, after which it is processed similarly to a
conventional soft encapsulated gelatin capsule.
[0007] More recently (
Packaging Technology, March/April 1987, Vol 17, No. 2, pp. 4, 7 and 16), equipment and methods for encasing
a pair of half-dose softly-compacted tablet-like preforms between converging soft
elastic gelatin films have been described. So far as is known, such equipment was
not successfully built and operated. Another example of such apparatuses is given
in IT-A-0 538 281, which forms the basis for the preamble of claims 1 and 11.
[0008] A need exists for a way for the soft elastic gelatin capsule industry to support
and service the tablet manufacturing industry in providing improved film enrobed tablets
without disturbing the existing working relationships between those industries. This
invention addresses those needs and, in so doing, provides an improved tablet product.
[0009] This invention provides improved methods and equipment according to claim 1 and claim
11 which are readily adaptable to and implementable with existing procedures and machinery
in the soft elastic gelatin capsule manufacturing industry to produce the improved
tablets. Implementation and practice of these aspects of the invention does not require
large scale replacement, reworking or remanufacture of existing soft elastic gelatin
encapsulation machinery or procedures, and can be accomplished rapidly and efficiently
without disruption of established business practices and relationships.
[0010] According to a product aspect of the invention, there is provided an enrobed tablet,
according to claim 8, having a core within a coating of ingestible, substantially
solidified polymer. The coating is characterized by two applied layers of preformed
film of the polymer which are sealed together along and terminate at a line encircling
the core and which conform to and tightly adhere to the core without openings in the
coating.
[0011] According to a further product aspect of the invention, there is provided a gelatin
enrobed tablet having a tablet core and a gelatin-based coating enrobing the core.
The coating is characterized by two layers of preformed gelatin which are sealed together
and terminate at a line encircling the core. The coating is further characterized
by having one or more of the following characteristics: it is comprised of gelatin
and a plasticizer present in a weight ratio of from about 3:1 to about 15:1, it conforms
to the core contours and has no openings in it, it tightly adheres to the core and
is hard in the finished tablet, it tightly adheres to the core and has its seal line
either substantially aligned with a plane of symmetry of the core or substantially
disposed in a plane which includes an axis of symmetry of the core, or it adheres
sufficiently tightly to the core that it cannot mechanically be removed from the core
without removal of a part of the core.
[0012] Also described is an improved soft elastic gelatin composition useful to form the
enrobing film for the presently preferred article of manufacture. The composition
comprises gelatin and a plasticizer in a weight ratio of from about 3:1 to about 15:1,
the balance being comprised of water and such pigments as may be desired. This invention
also provides improved film compositions for use in enrobing tablets and other things
for various purposes. The compositions include a soft elastic gelatin film compositions
which provides a securely bonded enrobement around a solid tablet, thereby providing
a tablet having enhanced tamper-evident properties.
Brief Description of the Drawings
[0013]
FIG. 1 is a top plan view of a gelatin film enrobed tablet of caplet configuration
which is the presently preferred product produced by practice of this invention;
FIG.2 is an end elevation view of the gelatin film enrobed caplet shown in FIG. 1;
FIG. 3 is a cross-section view taken along line 3-3 in FIG. 2;
FIG. 4 is a cross-section view taken along line 4-4 in FIG. 3;
FIG. 5 is a side elevation view of a gelatin film enrobed caplet in which the enrobing
film is uniformly colored over the entire extent of the product;
FIG. 6 is a side elevation view of a gelatin film enrobed caplet in which the enrobing
film located on one side of a longitudinal plane of symmetry of the caplet is of one
color, and the film lying on the other side of that plane of symmetry is of a different
color;
FIG. 7 is a top plan view of a film enrobed round, but not spherical, tablet provided
as another product of this invention;
FIG. 8 is a cross-section view taken along line 8-8 in FIG. 7;
FIG. 9 is a cross-section elevation view of another round tablet which is another
product of this invention and which has, in top plan view, an appearance similar to
that shown in FIG. 7;
FIG. 10 is a top plan view of an oval film enrobed tablet which is another product
of this invention;
FIG. 11 is a cross-section view taken along line 11-11 in FIG. 10;
FIG. 12 is a cross-section elevation view of another oval tablet which, in top plan
view, has a configuration like that shown in FIG. 10;
FIG. 13 is a simplified depiction of presently preferred apparatus useful to film
enrobe tablets;
FIG. 14 is a simplified elevation view of tablet feeding mechanisms useful with the
apparatus shown in FIG. 13;
FIG. 15 is a simplified fragmentary perspective view of a tablet feeding mechanism
for a production form of the apparatus and process depicted in FIG. 13;
FIG. 16 is an enlarged perspective view of a portion of the feeding mechanism shown
in FIG. 15;
FIG. 17 is a fragmentary elevation view of the presently preferred tablet guide tubes
provided between the intermediate and final tablet feed mechanisms shown in simplified
form in FIGS. 14 and 15;
FIG. 18 is a fragmentary, enlarged cross-sectional elevation view of the connection
of the upper end of the tablet guide tube shown in FIG. 17 to the intermediate stage
tablet feeder mechanism in the presently preferred production apparatus;
FIG. 19 is a fragmentary, somewhat simplified, cross-sectional elevation view of the
final stage tablet feeding mechanism and die rolls in the presently preferred apparatus;
FIG. 20 is a perspective view of one of the die rolls shown in FIG. 19;
FIG. 21 is a fragmentary, enlarged plan view of a presently preferred cavity and land
configuration useful in the die rolls shown in FIG. 20;
FIG. 22 is an enlarged cross-section view taken along line 22-22 in FIG. 21; and
FIG. 23 is a simplified top plan view of a portion of a presently preferred mechanism
for achieving proper positioning of caplet-style tablets in the final stage tablet
feeding mechanism shown in FIGS. 15 and 16.
Description of the Illustrated Embodiments
[0014] In broad terms, this invention concerns the coating of tablets, other solid dosage
forms, and a variety of solids by enrobement with films of gelatin or other sealable
polymers by an enrobement process which uses coacting die techniques in which the
articles to be enrobed are introduced individually between two sealable films positioned
between opposing matching dies configured to cause the films to stretch and deform
around each introduced article so that the films move into contact with each other,
are sealed to each other and, as sealed, are severed from the film webs to provide
individual film-enrobed end products.
[0015] The hermetically-sealed applied-film coating around the tablet or other solid core
of the enrobed product can be treated after production for controlled release or enteric
release. Due to the continuous nature of the applied-film coating, individual coated
units provide an assurance of consistent product performance.
[0016] In the following description, unless the usage context indicates otherwise, the term
"tablet" is used in its broad sense to mean a solid, hard, unitary pellet containing
one or more active ingredients, which pellet is of such size as to be administered
by an intended user and is of desired geometry; the term includes such things having
caplet configuration, which things are often referred to simply as "caplets".
[0017] The product in FIGS. 1-4 has a core 11 and a hard gelatin coating 12 which fully
encloses the core. The coating conforms tightly to the contours of the core and is
adhered tightly to the surfaces of the core over the entire exterior surface extent
of the core. Coating 12 is defined by layers 13 and 14 of soft elastic gelatin film
which are applied to opposite sides of the core and which are sealed together, in
an essentially edge-to-edge manner, along a seal line 15 which encircles the core.
Seal line 15 preferably is substantially coincident with a longitudinal plane of symmetry
16 of the core. After being applied to and sealed together around the core, layers
13 and 14 dry to a hard glass-like state in which the coating is securely bonded to
the core. The gelatin used to form layers 13 and 14 is formulated to produce such
a finished coating.
[0018] Preferably, applied gelatin layers 13 and 14 are colored differently from the color
of core 11 itself. If both applied coating layers are of the same color, the resulting
product is a monocolored gelatin film enrobed caplet 17 shown in FIG. 5. On the other
hand, if applied gelatin layers 13 and 14 have different colors, the resulting product
is a bicolored gelatin film enrobed caplet 18 as shown in FIG. 6.
[0019] Gelatin layers 13 and 14 preferably are provided as portions of two soft elastic
gelatin films which, as cast in the machinery described below and presented to the
core for enrobement of the core, have a thickness in the range of from 0.005 inches
to 0.04 inches. If equipment of different definition from that described below is
used, films of substantially greater thickness can be handled. As applied to the caplet
core and as dried thereon, the layers 13 and 14 are of somewhat smaller thickness.
[0020] Caplet core 11 can be manufactured to the desired size, shape, and composition at
a facility segregated from the facility where gelatin film enrobement of the caplet
occurs. Caplets generally are of geometrically similar configuration and are of elongate,
round-ended configuration in plan view (see FIG. 1) and have a cylindrical peripheral
surface 20 which has an oblong cross-sectional configuration. Surface 20 extends along
the opposite sides 21 and around the opposite ends 22 and 23 of the caplet. The distance
between the parallel sides 21 of the caplet is its width, and the distance between
the extremities of ends 22 and 23 is the length of the caplet. The height of the caplet
is the dimension of the caplet perpendicular to its width and length. As shown in
FIG. 2, the caplet has curved top and bottom surfaces 24 and 25, respectively. A caplet
has three orthogonally oriented planes of symmetry. The major plane 16 of symmetry
of the caplet lies parallel to the width and length of the caplet midway between the
top and bottom extremities of the caplet, midway of the height of cylindrical caplet
peripheral surface 20. A second caplet longitudinal plane of symmetry 16' lies parallel
to the length of the caplet and perpendicular to plane 16 centrally of the width of
the caplet. Plane 16 may correspond to the parting plane of the dies used to form
the caplet. As shown in FIG. 2 which is an end view of caplet core 11 turned on its
side, a caplet has a diagonal dimension D.
[0021] While gelatin enrobed medicinal caplets constitute the presently preferred product,
the utility and operability of the invention has been demonstrated with tablet cores
of other configurations. Other exemplary products include a round planform film coated
tablet 27 shown in FIG. 10 which can have either an oval or elliptical cross-section
as shown in FIG. 8 or the cross-sectional configuration shown in FIG. 9 in which the
round core 28 has a circularly cylindrical peripheral surface 29 and substantially
identical curved top and bottom surfaces 30. As shown in FIGS. 8 and 9, products 27
or 31 (FIG. 9) have an applied film coating completely around their exterior surfaces,
which coatings are defined by cooperating top and bottom layers 13 and 14 of applied
film which are connected together at a seam line 15 which extends circumferentially
of the product at a plane of symmetry 16, which encompasses the greatest cross-sectional
area of the product core. The seam line can be located at other places on the product
core.
[0022] Similarly, as shown in FIGS. 10 through 12, a film enrobed product 33 or 34 can have
an oval configuration when viewed from the top (see FIG. 10) and either a lengthwise
cross-sectional configuration (product 33) which is the same as that shown in FIG.
8 for product 27 (see FIG. 11) or a lengthwise cross-sectional configuration (product
34) which is the same as that shown in FIG. 9 for product 31.
[0023] FIGS. 8, 9, and 10 show that the enrobed tablets there illustrated have other planes
of symmetry 16' which are perpendicular to the major planes of symmetry 16 and are
either disposed diametrically (FIGS. 7-9) or longitudinally (FIGS. 10-12) of the tablets.
Film enrobed tablets can be produced with seam lines disposed in symmetry planes 16'
of the caplet (FIGS. 1-6), round (FIGS. 7-9) and oblong or oval (FIGS. 10-12) tablets
if such seam placement is desired.
[0024] An applied-film enrobed product produced by the registering, preferably rotary, die
process described in greater detail below has a characteristic signature. That signature
is a very slight thickening of coating 12 along seam line 15; see FIGS. 3, 4, 8, 9,
11 and 12. Principally for aesthetic reasons, it is preferred that seam line 15 lie
in the major 16 or secondary 16' plane of symmetry of the core of a medicinal or similar
product. Coincidence of the seam line with a plane of symmetry is particularly preferred
where the applied-film enrobed product is bicolored (see product 18 in FIG. 6) for
any one of various reasons including product identifiability.
[0025] FIGS. 13 through 23 illustrate the preferred process for making applied-film enrobed
articles according to this invention, including the various kinds of medicine tablet
products shown in FIGS. 1 through 12. FIGS. 13 through 23 also show preferred equipment
useful to practice the preferred manufacturing method. Except for the nature of the
core feeding mechanism, the basic aspects of the preferred process and manufacturing
equipment are shown in FIG. 13. The manufacturing process and equipment create and
use first and second films 36 and 37 of soft elastic gelatin of selected thickness
and composition, and a pair of matching dies 38 and 39 (which preferably are rotary
dies) and between which films 36 and 37 pass adjacent the location where a core feed
device 40 cooperates with at least one and preferably both of the films and dies.
In the preferred manufacturing process and manufacturing apparatus, the core feeding
mechanism is arranged to introduce the cores to the films in the working area between
the dies so that each core contacts both films essentially simultaneously. Except
for the specifics of the dies and the core feeding mechanisms used in the practice
of this invention, the machinery and processes depicted in FIG. 13 will be familiar
to workers skilled in the manufacture of soft elastic gelatin capsules and in the
design and operation of machinery for making such capsules.
[0026] As shown in FIG. 13, films 36 and 37 are individually cast on separate rotating casting
drums 42 and 43 in a continuous manner by introduction of liquid gelatin to the outer
casting surface of each drum from a liquid gelatin dispensing device 44 of known nature.
Liquid gelatin is supplied to each dispensing device from a respective container 45
in which the gelatin is kept liquid at an elevated temperature by a heater 46, such
as an electrical heater. Each container 45 is airtight so that liquid gelatin can
be moved from the interior of the container to the adjacent gelatin dispensing device
44 through a transfer tube 47 under the effect of compressed air introduced to the
container through an inlet tube 48. Gravity feed of liquid gelatin to the dispensing
devices can be used, if desired.
[0027] Each casting drum 42, 43 is cooled by circulation of an appropriate coolant. Hence,
the liquid gelatin introduced to the moving casting drum surface solidifies on the
drum casting surface sufficiently to form film 36 or 37 adequately that the film can
be led continuously from the respective casting drum to dies 38 and 39 along a desired
path. The path of movement of the cast gelatin film is through a lubricant bath 50
via a roller 51 and thence to a driven tractor roll 52. The lubricant in bath 50 is
applied principally to the reverse surface of the film, which will not be contacted
with the other film between die rolls 38 and 39. The outer surface of tractor roll
52 preferably has a traction layer 53 which enables the traction layer to co-act without
slippage with the reverse surface of the gelatin film. As the gelatin film passes
from each tractor roll to the adjacent die 38 or 39, a thin layer of lubricant remains
on the film reverse surface to prevent the die and the film from sticking to each
other.
[0028] As shown in FIG. 13, dies 38 and 39, together with the cooperating portion of the
core feed mechanism 40, are symmetrically disposed relative to each other about a
functional center plane 54 of the apparatus. The portion of the core feed mechanism
immediately adjacent to the cooperating dies is a core feed horn 56 disposed upon
functional center plane 54 in association with a pair of shaped metal heater blocks
57 which extend across the width of the adjacent gelatin film. Each heater block preferably
includes an electrical resistance heater element 58 (see FIG. 19). The heater blocks
are in close proximity to the core feed horn 56 and to the die rolls for contacting
the obverse surface of the adjacent gelatin film in that portion of the film path
where the film preferably then is wrapped around the adjacent die roll. The heater
blocks heat the gelatin films to a desired temperature which is important to the topics
of self-timing operation of the dies and feed mechanism and of the character of the
enrobement of each product core by the gelatin films, both topics being discussed
in greater detail below. Each heater block 57 has a curved film-contacting surface
59 for contact with the obverse surface of the moving gelatin film as closely as possible
to the point at which individual product cores emerge from the lower end of the wedge-shaped
lower portion of core feed horn 56 substantially at the nip of dies 38 and 39. The
die nip is the place where films 36 and 37 are brought into contact with each other
by the dies.
[0029] At the location where die rolls 38 and 39 and core feed horn 56 cooperate closely
with each other, the product cores are individually contacted with the controllably
heated obverse surfaces of the converging gelatin films 36 and 37. The films are stretched
around the opposite sides of the cores symmetrically relative to apparatus center
plane 54, thereby to define the applied layers 13 and 14 of the coating 12 of the
desired product. The gelatin films are sealed to each other along the seam line 15
of the product and the thus conjoined and adhered films are cut to allow the gelatin
enrobed products (shown as articles 60 in FIG. 13) to separate from a perforated gelatin
web 61 which emerges from between dies 38 and 39. Web 61 is formed by the adherence
of gelatin films 36 and 37 to each other by the dies. After emerging from between
the dies, the web passes between a pair of driven mangle rolls 63 which have surface
speeds slightly greater than the surface speeds of dies 38 and 39 so that web 61 is
stretched between the dies and the mangle rolls. This stretching of the web enables
the gelatin enrobed product cores, i.e., products 60, to self-separate from the web
and to move, with the assistance of product guides 64 (cooperating with the web between
the dies and the mangle rolls), into product receptacles 65 where the products are
collected before undergoing such further processing as may be necessary. Further processing
steps may include washing of products 60 to remove any residues of lubricant applied
to the gelatin films in baths 50, final drying, or perhaps application of timed release
or enteric release coatings as appropriate. The web 61 emerging from mangle rolls
63 is collected in a receptacle 66.
[0030] FIG. 14 generally illustrates a preferred core feeding mechanism 40 useful with and
as a part of the equipment shown in FIG. 13. Feeding mechanism 40 includes a first
stage core feeder 67, an intermediate feeder 68, and a final feeder 69 of which core
feed horn 56 is a component. The intermediate feeder and most of the structure of
final feeder 69 are located in an enclosure 78 which has an inlet opening 76 in its
top. First stage core feeder 67 includes a hopper 70, preferably having a closable
cover 71, into which large quantities of cores for products to be film enrobed are
introduced. Hopper 70 discharges cores therefrom to intermediate feeder 68 via a discharge
72 from the hopper. The hopper is secured to a support 73. A vibrator 74 is connected
to the bottom of hopper 70 to agitate cores in the hopper so that cores emerge as
desired from hopper discharge 72 to pass through opening 76 in the top of enclosure
78. Where the products produced are to be film enrobed medicine tablets and the like
in which it is desired that the applied film coating on each tablet tightly adhere
to the tablet surfaces, it has been found to be important that the tablets, when finally
introduced to contact with gelatin films 36 and 37, are as free of excessive dust
particles as possible. The presence of dust particles on the tablet cores or on the
obverse surfaces of the gelatin films applied around the tablet cores can result in
imperfect sealing of the applied gelatin layers 13 and 14 to each other. Therefore,
dedusting procedures are practiced in association with the intermediate and final
stages of core feed mechanism 40.
[0031] The discharge 72 of hopper 70 leads to an inlet 76 below which is an open top intermediate
feeder box 77 movably mounted in the upper portion of a dust-containment enclosure
78. The principal function of intermediate feeder 68 is to load individual product
cores into a plurality of core downtubes 79 which connect to respective vertically
disposed core passages 80 formed within core feed horn 56. Such loading of cores from
box 77 to downtubes 79 is achieved by laterally shaking or vibrating box 77; this
is accomplished by coupling the box to a stationary support bracket 81 via a suitable
shaker drive device 83. The support bracket is inside enclosure 78 which is, in turn,
mounted in any convenient way to a foundation 82. Preferably, the amplitude of oscillation
of box 77 is greater than the amplitude of oscillation of the bottom of hopper 70.
The upper ends of core downtubes 79 connect to the bottom of box 77 via suitable openings
85 as shown in FIG. 18. Dust either introduced to the interior of box 77 with the
cores or generated within the box by agitation of the product cores is extracted from
the interior of enclosure 78 through a duct 88 which is connected to a suitable source
of vacuum.
[0032] Downtubes 79 are located within enclosure 78. Since box 77 is oscillated laterally
relative to enclosure 78, downtubes 79 are flexible. The upper ends of the flexible
downtubes connect to the bottom wall of box 77 around respective ones of openings
85.
[0033] The presently preferred form of downtube 79 is a length of tubular, helically wound
spring, the inner diameter of which is sufficiently large to enable cores such as
caplets to move readily along the lengths of the downtubes and into respective ones
of passages 80 to which the lower ends of the downtubes are coupled. To facilitate
dedusting of cores moving through downtubes 79, the helical springs used to define
the downtubes are not tightly wound but rather, as shown in FIGS. 17 and 18, are defined
with slight spacing between adjacent turns of the spring helix. It is preferred that
at least the inner surfaces of each downtube be coated with a material having a low
coefficient of friction, such as tetraflouroethylene.
[0034] It has been found that caplets, because of their geometry, feed best from box 77
to downtubes 79 when the openings 85 through the bottom of box 77 to the respective
downtube are conically flared, concave upwardly, in the manner of a funnel as shown
87 in FIG. 18. It will be apparent that the size and geometry of the surfaces defining
the openings from box 77 to the respective core feed downtubes are defined as a function
of the geometry of the cores which are to be handled.
[0035] In handling different cores, an objective may be to cause the seam line 15 between
the applied gelatin layers of the finished enrobed cores to lie in either the major
plane of symmetry 16 of the core or the secondary plane of symmetry 16' of the core.
It has been found, particularly in the instance of caplet cores, that particular attention
is to be given to the handling of the cores in the final core feeder to cause the
cores to be properly aligned relative to the dies. Such alignment is important to
the desired coincidence of seam line 15 with the core major plane of symmetry. It
has been found that causing the core downtubes to be sloped, rather than vertical,
over a portion of their lengths between the intermediate feeder and the top of core
passages 80 significantly improves the probability that caplet cores will have proper
alignment with the die cavities upon contacting the gelatin films as the caplet cores
emerged from the lower ends of passages 80. It is preferred that a core alignment
mechanism be incorporated into the core feed horn 56. Such a mechanism 90 is shown
generally in FIGS. 14 and 15, in more detail in FIG. 16, and in greatest detail in
FIG. 23. Mechanism 90, as illustrated, is arranged to cause cores introduced to the
nip of dies 38 and 39 to have their major planes of symmetry 16 aligned with the die
nip line so that the seam lines 15 between the applied film layers on the finished
products lie substantially in the major plane of symmetry of the product cores. The
principles of mechanism 90 can be used to provide a core alignment mechanism useful
to cause tablet cores to have their secondary planes of symmetry 16' aligned with
the die nip line.
[0036] An upper portion 91 (see FIG. 23) of each core passage 80 in core feed horn 56 has
a circularly cylindrical configuration. A lower portion 92 of each passage has a cross-sectional
configuration which the same shape as, and is slightly larger in dimension than the
cross-sectional configuration of the core of interest. The configuration of the passage
lower portion is oriented in horn 56 so a core in that passage portion is aligned
with its major plane of symmetry parallel to and midway between the axes of rotation
of dies 38 and 39. The location of the transition between the circular and core-contoured
portions of the length of each passage 80 is at a common height along the lengths
of the passages. As shown in FIGS. 16 and 23, the outer side surfaces of the feed
horn which are disposed parallel to the axes of rotation of the adjacent dies are
recessed 93 such that the vertical base surface 94 of each recess intersects the circularly
cylindrical upper portion 91 of each core passage 80. However, the recess depths are
defined so that the plane of surface 94 of each recess lies outwardly of the core-contoured
lower portion 92 of each passage 80. That is, the elongate recess 93 formed in each
side surface of core feed horn 56 intersects the lowermost portion of the circularly
cylindrical upper portion 91 of each passage 80, but it does not have a depth sufficient
to extend to the adjacent wall of the core-contoured lower portion 92 of each passage.
[0037] A belt 95, which preferably is defined by a suitably sized rubber O-ring, is engaged
between a pair of support pulleys 96 disposed one adjacent each of the opposite ends
of the core feed horn in the plane of recesses 93. The opposite parallel legs 98 and
99 of the belt loop are disposed in recesses 93 sufficiently close to the recess vertical
surfaces 94 that they pass in chordlike manner across diametrically opposite parts
of the lower portion of the circular upper part of each passage 80 and the spacing
between the opposite belt loop legs is less than the width of caplet core 11, e.g.
A shaft 100, to which one of pulleys 96 is mounted, is rotated in a desired direction
by operation of a motor 101. During times when core feed mechanism 40 is operated,
motor 101 is also operated. Accordingly, belt 95 has one of its legs 98 moving in
one direction across one outer portion of the lower end of the circular part of each
passage 80 and has its opposite parallel leg 99 moving in the opposite direction across
an opposite outer portion of the same part of the same passage.
[0038] As shown in FIG. 23, if a caplet core 11 approaches the upper end of core portion
92 of passage 80 aligned transversely of the major dimension of the cross-sectional
shape of the passage lower portion, it cannot enter the passage lower portion. However,
as such a misaligned caplet core approaches the passage lower portion 91, it engages
the oppositely moving legs 98, 99 of belt 95 and, because of the opposite directions
of motion of the belt legs, is turned about its length in passage upper portion 91
until it is angularly positioned so that it can enter passage lower portion 92. As
the caplet is turned in the circular part of passage 80 so that it can enter into
the lower portion of the passage, it quickly disengages itself from contact between
the oppositely moving belt legs and quickly passes between those belt legs into the
passage lower portion. The dimensions of the passage lower portion are slightly larger
than the cross-sectional dimensions of the caplet core so that the core can move freely
under the bias of gravity and other influences downwardly through passage portion
91 while having its major plane of symmetry substantially coincident with the major
plane of symmetry of the passage lower portion. When the caplet emerges from the lower
end of passage 80 into contact with gelatin films 36 and 37, the major plane of symmetry
of the core will lie substantially in the plane of symmetry 54 of the enrobing apparatus.
As enrobed by the gelatin films, the caplet or other tablet core will have the seam
line 15 between the layers of gelatin applied to it substantially coincident with
the core major plane of symmetry 16. The core alignment mechanism operates so quickly
in a tangential manner upon cores in passages 80 that the mechanism has no discernible
effect upon the free movement of cores along the passages under the influence of gravity
and the height and weight of the core column.
[0039] If the products 60 to be produced in the enrobing apparatus are to have their seam
lines 15 between applied film layers 13 and 14 lying in the secondary planes of symmetry
16' of the cores, then a suitably defined different core alignment mechanism can be
used. For example, in such a different mechanism, the passage lower portions 92 could
have the same shape as shown in FIG. 23 Thus, film enrobed medicine tablets having
seam lines 15 aligned with either the major 16 or secondary 16' planes of symmetry
of the tablets can be provided as the products of this invention.
[0040] FIG. 16 also shows that, as preferred, a switch 104 can be mounted to the core feed
horn in association with each passage 80 for blocking the passage at a desired location
along its length. Preferably that location is below the location of the belt 95. The
switches can be bistable electrical or pneumatic devices which, when in one state,
allow a plunger to extend sufficiently into the cooperating passage 80 to prevent
the movement of cores through the passages, but which, when in the other state, cause
the plunger to be withdrawn from the passage.
[0041] FIGS. 19 through 22 show details of the drum-like dies 38 and 39 which are used for
producing the preferred product 10 of this invention. Dies 38 and 39 are essentially
identical. Each die is arranged to be rotated about an axis. Die 39 is positively
driven at a desired angular velocity, and die 38 is slaved to driven die 39 by gears
(not shown) between the dies so that dies 38 and 39 rotate synchronously in opposite
directions about their respective axes of rotation. Since dies 38 and 39 are identical,
except to the extent described above, a description of die 39 shall constitute a description
of both dies.
[0042] Die 39, as shown in FIG. 20, has a circularly cylindrical working surface 107 extending
along the length of the die drum between its opposite ends. There are defined in working
surface 107 a plurality of recesses 108 each of which cooperates with a corresponding
recess in the other die for defining a corresponding cavity between the dies as they
turn about their axes of rotation into and out of substantially matching coaction
with each other. Since, as shown in FIG. 19, dies 38 and 39 are used to produce products
10 which have caplet cores, the planform configuration of each recess 108 in each
die has a geometry which corresponds to the top plan view of product 10 as shown in
FIG. 1 but is somewhat oversized in width, length and depth relative to such product.
Even as enwrapped and enrobed between films 36 and 37 within each cavity formed by
cooperating recesses, the preform and films within the cavity are loose within the
cavity and do not bottom-out or otherwise significantly contact the bottom or sides
of the recesses. Each recess 108, as formed in a die working surface 107, is surrounded
by a raised rim 109, the end of which is spaced from the adjacent die working surface
and which makes essentially direct contact with the corresponding feature of the adjacent
die as the dies turn synchronously about their respective axes. The edges of each
recess rim, both toward and away from the corresponding recess, are rounded to desired
small radii of curvature.
[0043] Each rim 109 of a recess 108 for use with caplets 12 has parallel opposite sides
110 aligned with the circumference of die 39 and arcuately configured portions 111
at each of the opposite ends of cavity 108 (see FIG. 21). For reasons which are described
more fully below, the rounded end portion 111 of each cavity rim 109 has a base curvature
in which the radius of the arc of the rim is substantially equal to one-half the width
of cavity 108 between straight rib portions 110. At the extreme ends of each recess
108, a more curved arcuate portion 112, having a smaller radius of curvature, is centered
on the elongate center line of the recess. The more curved portion 112 of the peripheral
rim around each recess provides a supplemental volume (relief) 113 at each end of
the recess. The end of each recess rim 109 spaced away from die working surface 107
is a land surface in the die.
[0044] The supplemental volume at each end of a die recess can have a geometry different
from that shown in FIG. 21, if desired. For example, the supplemental volume, when
viewed along a line normal to the die working surface, can have a shape resembling
a rectangle wrapped around the principal contour of the recess end. The supplemental
volume shape which is most effective may and likely will vary with the shape and dimension
of the core with which the die recess cooperates in any given instance. The principal
significance of the supplemental volumes in a die recess is to assure that, in cooperation
with the size and shape of the relevant article preform being handled at any given
time and the orientation of that preform relative to the recess, the area of film
disposed over the recess within the recess rim, at the time the die moves in conjunction
with the other die to close the recess around the preform, is an area which is sufficient,
in connection with the thickness, composition and condition of that film, to accommodate
stretching of the film in all directions, without rupture of the film, to fully cover
the preform in conjunction with the action of the film overlying the matching recess
in the other die.
[0045] As shown in FIG. 20, a plurality of rows of recesses 108 are provided circumferentially
of die 39. The rows can be uniformly spaced from each other along the axial extent
of the die. In each row, the recesses are spaced at uniform intervals around the circumference
of the die with a preselected spacing "d" (see FIG. 21) between the outer portions
of recess rims 109 along the line of each row of recesses. Distance "d" is a relatively
small distance; it is as small as workable consistent with the functioning of lands
109 to seal films 36 and 37 around individual preforms and to cut the film-enrobed
preforms, with their gelatin enrobing layers sealed to each other, from web 61. Distance
"d" preferably is determined with reference to the thickness of the films passing
between the dies.
[0046] As shown in FIG. 20, two rows of teeth 115 are raised from die working surface 107
circumferentially of the die at each end of the die. The teeth on one die do not intermesh
with the corresponding teeth on the other die. Teeth 115 comprise traction tires on
the ends of each die for gripping the respective gelatin film which has a width transversely
of the film web greater than the axial length of the drum.
[0047] It is presently preferred that recesses 108 have their long dimensions aligned with
the circumference of the dies rather than with the axial extent of the dies. This
orientation of the recesses on the die working surfaces is consistent with the presently
preferred end-wise feeding of caplets 12 to the nip between dies 38 and 39 in the
manner shown most clearly in FIG. 19.
[0048] As seen from FIG. 19, caplets 12 are individually dispensed in a passive, unclocked,
self-timed manner into simultaneous contact with the heated obverse surfaces of gelatin
films 36 and 37 substantially at the nip between dies 38 and 39 where they cooperate
most closely with each other. The caplets emerge one at a time from the lower end
of a lower portion 92 of a core passage 80 in core feed horn 56; there is one passage
80 for each row of recesses around a die. Each passage 80 has its centerline defined
to intersect the centerline of the corresponding two rows of recesses 108 in the adjacent
dies 38 and 39. As stated above, passages 80 are aligned along the functional center
plane 54 of the core enrobing apparatus. Passages 80 open to the die nip area through
the substantially knife-edged lower end of the wedge-shaped lower portion of the core
feed horn. In each passage 80, caplets 12 are disposed lengthwise in end-to-end relation
to each other in a caplet column in which each caplet stands on the caplet below it
in the passage. The caplets in the lower portion 92 of each passage 80 have their
major planes of symmetry 16 aligned with apparatus center plane 54 for the reasons
described above with reference to FIG. 23.
[0049] The frequency at which individual caplets 12 emerge from the lower end of each passage
80 is a frequency which is self-defined within the enrobing apparatus. There are several
things which affect this unclocked dispensing of caplets and other tablet cores to
films 36 and 37 and to the rotary dies. These factors include the composition of the
gelatin material from which films 36 and 37 are cast, the thickness of films 36 and
37, film elasticity, film temperature at the point of contact of each core with the
films between the lower extent of the feed horn and the die nip, the tension in films
36 and 37 across recesses 108 as the films are engaged by each core, the adhesiveness
of the films to the dispensed cores, core mass and size, the number of cores in the
column of cores in each core passage 80, and the rate of advance of films 36 and 37
past the lower tip of the core feed horn. These factors are interrelated to each other
with greater or less degrees of directness.
[0050] Pertinent tension in the films is determined, among other ways, by the difference
in surface velocities of the dies as compared to tractor rolls 52. The surface velocities
of the dies are defined to be a selected slight amount greater than the surface velocities
of the tractor rolls. Another factor affecting film tension is the temperature of
the film. Film elasticity is interrelated to the film composition, the film thickness
and the film temperature. The extent to which the film obverse surfaces adhere to
the cores is a function, among other things, of the film surface temperature. For
cores of given mass, size and shape, there can be too few or too many cores in the
core column within passage 80 for the self-timing aspect of the core-to-film feed
operation to be achieved satisfactorily. One of the factors which affects the unclocked,
self-timed dispensing of cores to films 36 and 37 from passages 80 is the static head
of cores in the passages. These various factors and their interrelationships are discussed
more fully below.
[0051] Particularly in the instance of caplet cores, it has been found important to provide
the supplemental volumes 13 at the ends of die recesses 108. Caplets are a difficult
configuration of core in the context of the self-timed dispensing effect. Round cores,
or cores which are more round than they are of caplet configuration, are more readily
handled than caplets in the unclocked core dispensing arrangement shown in FIG. 19.
[0052] It has been found that, when the various factors and influences described above are
properly observed in relation to each other, tablet cores, even cores of caplet configuration,
can self-feed satisfactorily into contact with films 36 and 37 without positive injection
of the cores to the films and without other metering procedures being observed. The
lower end of the lowermost core in passage 80 effectively contacts films 36 and 37
at a location on the films where the films overlie die recesses positioned at about
the position of recesses 108' illustrated in FIG. 19. The gelatin film obverse surfaces,
being sticky by virtue of heat having been applied to the films from heating blocks
57, grab a core from the lower end of passage 80 and carry the grabbed core with the
films away from the lower end of the core feed horn. As this occurs, the films stretch
around the grabbed core within the corresponding recesses and, particularly where
the presently preferred gelatin formulation described above is used, conform closely
to the contours of the grabbed core and adhere to the core. Because each core is introduced
into contact with the films with the major plane of symmetry of the core aligned with
apparatus center plane 54, the films apply themselves to the core symmetrically about
the core major center plane 16 and form a seam line 15 around the core at a location
on the core which is essentially coincident with that major plane of symmetry. All
of these things occur as the dies continue to rotate following first contact of each
core with films 36 and 37. As a core enrobed between the gelatin films reaches and
passes through the point of closest contact of the dies with each other, the films
surrounding each core are sealed tightly together. Such sealing occurs due to the
self-adhesive nature of the films. Essentially concurrently with sealing of the films
tightly together thereby to define web 61, the lands defined by the ribs 109 which
surround each cavity 108 move into sufficient proximity to each other to cut the enrobed
cores from the web. At that point, products according to this invention are essentially
complete save for such washing and further drying operations, and perhaps further
coating operations, as may be desired.
[0053] The thickness of films 36 and 37 is a factor, among others, which affects the resiliency
of the gelatin films during the core enrobing process. The stretchability of film
over a core is also affected by film thickness. The minimum film thickness which can
be used for successful enrobement of cores is in turn affected by the type of gelatin
used to create films 36 and 37 and by the gelatin-liquid formulation. In rotary die
core enrobement apparatus of the kind described above, it has been found that films
having a thickness of from 0.02 to 0.04 inches thick worked well, although films having
a thickness of 0.01 inch were handled successfully. For practical purposes, it is
believed that gelatin films thinner than 0.005 will require the use of a specialized
coating system. As noted above, if equipment of definition different from that described
above is used, films of substantially greater thickness can be handled.
[0054] It has been found that the unclocked self-timed dispensing of stacked cores from
passages 80 to soft elastic gelatin films engaged over and between rotary dies of
the kind described above is relatively unaffected by die velocity. Surface speed of
the dies should not be so high as to exceed the ability of the cores in passage 80
to move under the bias of gravity into contact with the films passing the lower end
of the core feed horn at a frequency which corresponds to the effective frequency
at which recesses 108 pass the same place.
[0055] It has been found, particularly in the instance of caplet cores, that close spacing
between adjacent recesses 108 in each line of recesses circumferentially of the dies,
and the provision of supplemental volumes 113 in the ends of the die recesses, are
significant to eliminate the tendency of the die structure between adjacent recesses
from nipping at the lower ends of cores fed to films 36 and 37 through passages 80.
[0056] It has been found that the temperature of the gelatin films as they pass the lower
end of the core feed horn is significant to the fluidity of the gelatin film and its
ability to form a seal around cores dispensed to the films. The precise temperature
which is best in any instance depends upon film thickness and the gelatin formula.
Film temperature at and near the die nip is also affected by the geometry of the core
feed mechanism in cooperation with the dies, and by how far from the die nip location
the film heater blocks are located.
[0057] From experience with various gelatin formulations and film thicknesses, it has been
found that the core feed wedge temperature is best controlled and maintained within
a range of from 100° F. to 190° F. The precise temperature which is best used in any
given instance depends upon the gelatin formula and film thickness. Temperature should
be controlled within plus or minus 2° F. for optimum film sealing results.
[0058] Gelatin type, source, and formula have an impact upon film elasticity, the ability
of the films to adhere to cores dispensed to the films, and the adhesion of the films
to the dies. Gelatins with bloom values of from 150 to 180 are preferred, but it has
been found that gelatins having a bloom value in the range of from 120 to 250 can
be handled. Specific gelatins with blooms as high as 300 and as low as 100 can be
custom manufactured.
[0059] The adhesion of the gelatin film to the product core is significant in two ways.
In one way, adhesion of the film to a core produces a grabbing effect of the films
upon the core to self-time the dispensing of cores onto the films. The other aspect
of film adhesion is relevant during the product drying process where the applied gelatin
layers forming the gelatin coating around the enrobed product becomes an integral
part of the finished product and cannot, as presently preferred, be physically removed
without damaging the core. This is particularly important where the product to be
produced is a tamper-evident medicine tablet. It has been found that where the ratio
of plasticizer to gelatin in the initial gelatin formulation is about 1:5, a very
satisfactory tamper-evident gelatin film enrobed tablet is produced. Gelatin films
cast from gelatin formulations having gelatin to plasticizer ratios in the range of
from 3-1/3:1 to 15:1 will adhere to most tablet cores. Low ratios of plasticizer to
gelatin result in a brittle coating around the tablet core, while high ratios result
in a gelatin coating around the tablet which is flexible and can be peeled from the
tablet.
[0060] It has been found that substantially any gelatin formulation which can be used successfully
in the manufacture of soft elastic gelatin capsules containing flowable materials
such as powder, liquids or pastes, can be handled in the processes and apparatus of
this invention to produce applied-film gelatin coatings around a wide range of cores
or product preforms. In that context, gelatin formulations having by-weight compositions
of 32 percent to 50 percent gelatin, 17 percent to 35 percent plasticizer, 29 percent
to 44 percent water, and colorants and pigments in the range of from 0.1 percent to
3 percent can be handled. However, if a gelatin coating which adheres to the product
core is desired, then gelatin formulations having by-weight compositions of 40 percent
to 60 percent gelatin, 5 percent to 12 percent plasticizer, 35 percent to 50 percent
water, and colorants and pigments in the range of 0.1 percent to 3 percent should
be considered. Glycerin and sorbitol can be used as single plasticizers or in combination
with each other. In addition, other sugars and polyhydroxy compounds can be used as
additives and plasticizers. If a tamper-evident gelatin-coated medicine tablet is
the desired end product, then the ratio of plasticizer to gelatin in the gelatin formulation
should be in the range of about 1:5. It will be appreciated that the range and versatility
of gelatin film formulations which can be handled by the present technology makes
possible the manufacture of gelatin coated tablets or other products which have peelable
coatings, as where the applied-film coating is desired around the product core to
serve as a protectant or preservative for the core.
[0061] The present invention provides significant advantages over previously known techniques
for gelatin coating medicine tablets and the like by dipping processes. In order for
dipping processes to be practiced, the gelatin baths into which tablets and the like
are dipped must be in a liquid state. That means that such gelatin baths must contain
substantial unbound water which is free to react with the active or other ingredients
in the medicine tablets. In the practice of the present invention, on the other hand,
substantially dry gelatin films exhibiting substantially low water activity are used
to produce the desired gelatin coating around the medicine tablet core. In these gelatin
films, the water molecules are significantly more bound to the other constituents
of the film. The result is that there are few water molecules in the fluid which are
free to react with the cores around which the films are applied. Also, applied gelatin
films used in the practice of this invention are substantially cooler when they come
into contact with medicine tablet cores than is the case of tablets dipped in gelatin
baths which must be at relatively high temperature. Further, this invention can provide
products in which there is no air trapped between the applied gelatin coatings and
the cores to oxidize the core or any of its constituents.
[0062] In the case of other applications of the technology provided by this invention, the
applied-layer coating may not conform precisely to the thing enrobed, so that the
coating generally conforms to the contour of the thing coated, and the coating may
not be bonded or adhered to the thing coated. Other films which have been shown to
be useful in this broader context include films defined principally by polyvinyl alcohol.
Other films which are believed to be useful include films made from starches, modified
starches, alginates, modified gelatin, acrylates, polyvinyl pyrrolidone, cellulose
derivatives both esters and ethers, and polysiloxanes, among others.
[0063] Products so packaged are often displayed for sale on hooks or rods, rather than on
shelves. Such packages are characterized by a substantial width of film-covered card
extending in all directions in a common plane from the packaged articles(s).
[0064] In a product according to this invention, by contrast to blister packaged and shrinkwrap
packaged products, the applied-film coating around the thing coated is a package which
has essentially no flange extending away from the coated thing. Also, the packaging
coating can be part of the product itself, as in the instance of the presently preferred
gelatin coated caplet 10 described above, instead of a package to be discarded when
the product is used. The applied films are effectively sealed together in edge-to-edge
manner. It will be seen, therefore, that this invention provides a new kind of applied-film
product package which is materially different from previously known product packages,
including gelatin-dipped medicine tablets.
[0065] Workers skilled in the art to which this invention pertains will appreciate that
the foregoing descriptions of presently preferred and other embodiments of various
aspects of this invention are primarily illustrative and exemplary and are not an
exhaustive catalog of all of the ways in which the invention can be embodied. Such
workers will appreciate the modifications, variations and alterations can be made
to the products, formulations, procedures, and apparatus which has been described
without departing from the scope of this invention.
1. A process for enrobing individual medicine tablets (11) of substantially uniform size
and shape within a coating (12) of an ingestible polymer, in which two preformed films
(36, 37) of the polymer are moved into convergence with each other by being wrapped
around portions of the circumferences of respective ones of a pair of similar, cylindrical,
locally recessed (108) rotary dies (38, 39), in which the dies register at a horizontal
nip line where the films move downwardly, in which the tablets are individually introduced
between the films at the nip where the films are applied by the dies around the tablets
and are sealed together and severed along encircling lines (15) about and closely
contiguous to the tablets, and characterized by establishing in the films as disposed
across the die recesses desired conditions of film deformability, tension and adhesivity
of the films to the tablets and to each other, and presenting the tablets individually
into contact with the moving films proximate the nip in line with said die recesses
so that the films are free to deform laterally around the article so that the tablet
is grabbed and drawn into the nip in the die recess by the moving films in an unclocked
self-metering manner.
2. The process of claim 1 wherein the tablets (11) are arranged in a stack in which the
bottom tablet in the stack makes contact with at least one of the films (36,37).
3. The process of claim 2 wherein the tablets (11) are introduced into the nip by disposing
the stack in contact at one end with at least one of the converging moving films adjacent
to the nip so that the end tablet of the stack in contact with the moving film is
grabbed and drawn into the nip thereby.
4. The process of claim 3 wherein the end tablet of the stack is contacted with the moving
film by gravity.
5. The process of any one of claims 2 to 4 wherein each tablet (11) is aligned in the
stack in a desired relation to the nip line.
6. The process of any one of claims 2 to 5 wherein the number of tablets (11) in the
stack is maintained within a selected range.
7. The process of any one of the preceding claims wherein the tablets (11) are supplied
to the films (36, 37) as a column of tablets of selected height in a vertical passage
(92) opening to the nip at a location between corresponding die recesses (108), each
tablet in the column being free to move along the passage under the bias of gravity
and the weight of other tablets above it in the column, and by selecting the film
thickness, formulation, temperature and tension and the column height in coordination
with each other so that the tablets self-dispense from the passage to substantially
simultaneous contact with the films in synchronism with movement of corresponding
opposite die recesses into alignment with each other in response to rotation of the
dies.
8. The process of any one of the preceding claims wherein the polymer is gelatin-based
and comprises gelatin and a plasticizer present in a gelatin-to-plasticizer weight
ratio in the range of from about 3:1 to about 15:1.
9. The process of any one of the preceding claims wherein the polymer comprises gelatin
in the range of from about 40 percent to about 60 percent by weight, a plasticizer
in the range of from about 5 percent to about 12 percent by weight, the balance comprising
water and such pigments and colorants as may be desired.
10. The process of claim 1 for enrobing an article preform (11) with a substantially solidified
polymer, in which at least two sheets of a substantially solidified polymer (36, 37)
are drawn together to form a nip between the converging sheets, the process comprising
the steps of: (a) placing a stack of complete article preforms in contact at one end
with at least one of the converging sheets adjacent to the nip so that the end preform
of the stack in contact with the sheet is grabbed and drawn into the nip by at least
one of the converging sheets, and (b) sealing the two converging polymer sheets about
the grabbed and drawn preform to enrobe the preform at least partially in the sheets.
11. Apparatus suitable for enrobing individual medicine tablets (11) of selected size
and shape by introducing the tablets individually between two films (36, 37) of an
ingestible polymer which move along respective paths which converge at a nip between
a pair of mating synchronously driven cylindrical rotating dies (38, 39) around portions
of which the respective films are wrapped over die surfaces in the circumference of
which are formed a respective line of spaced recesses (108) each of which is cooperable
with a similar recess in the other die to form at the nip a cavity sized to receive
one tablet (11) loosely therein, the dies also coacting at the nip to seal the films
together around each tablet along a line (15) about and closely contiguous to the
tablet and to sever the films essentially along that line, and characterised in that
film conditioning means (52, 57, 58) cooperates with the film paths to create in the
films as disposed across the die recesses predetermined conditions of film deformability,
tension and adhesivity to the tablets and to each other, and by an unclocked self-metering
tablet dispenser (56, 91, 92) which is operable as defined in the process of claim
1 and which is located between the dies (38, 39) substantially at the nip for presenting
tablets individually to essentially simultaneous contact with the films (36, 37) for
take-up and transport by the films at film locations overlying corresponding die recesses
(108) so that each presented tablet moves with the films from the dispenser in a cavity
to and through the nip and the films are deformed and stretched in the cavity around
the tablet into enrobing engagement between the films.
12. The apparatus of claim 11 wherein each tablet (11) has at least one plane of symmetry
(16, 161), and wherein the dispenser (56, 91, 92) and the dies (38, 39) are cooperatively
coordinated to cause the film seal line (15) around a tablet to lie essentially in
one of those planes.
13. The apparatus of claim 11 or claim 12 wherein a registration line between the dies
is substantially horizontal and the dispenser (56, 91, 92) includes a substantially
vertical passage (92) through which tablets can move and which opens a lower end thereof
toward the die registration line proximately above the registration line, the passage
being sufficiently long adjacent the lower end thereof that a plurality of tablets
can be disposed in the passage in a column having its lower end at the passage lower
end.
14. The apparatus of claim 13 wherein each tablet (11) in the column in the passage (92)
is supported by the tablet below it and the lower-most tablet in the column is free
to extend through the passage lower end into contact with the converging films (36,
37).
15. The apparatus of any one of claims 11 to 14 wherein the dispenser (56, 91, 92) is
sensitive, inter alia, to selected characteristics of the tablets (11) including their mass and the number
of tablets stacked in a column in the passage (92).
16. The apparatus of any one of claims 11 to 15 wherein the dispenser (56, 91, 92) includes
the spacing between adjacent recesses (108) along the respective lines circumferentially
of the dies (38, 39).
17. The apparatus of any one of claims 11 to 16 wherein the dispenser (56, 91, 92) operates
to present the tablets (11) into contact with the films (36, 37) with each tablet's
selected plane of symmetry (16, 161) substantially coincident with a plane (54) on which the dispenser is centred, whereby
the films (36, 37) connect at a seam line (15) between the films substantially in
the tablet selected plane of symmetry.
18. An article, as for example a tablet, produced by the process of any one of claims
1 to 10 enrobed between two films of substantially solidified polymer (e.g. ingestible
polymer) which are sealed together along and terminate at a line encircling the tablet
and adhere to the tablet, the films being stretched from an undeformed state around
the tablet from opposite sides of the tablet into contact with each other along the
line.
19. A composition castable into a film specifically adapted for use in the process of
any one of claims 1 to 10 or in the apparatus of any one of claims 11 to 17, the film
being capable of being deformed around a medicine tablet and of bonding to a second
film of similar composition, the composition comprising a plasticizer, a base compound,
and a solvent compatible with the plasticizer and the base compound, the base compound
being selected from gelatins, modified gelatins, starches, modified starches, alginates,
acrylates, polyvinyl pyrolidine, polyvinyl alcohol, cellulose derivatives, both esters
and ethers, and polysiloxones.
1. Verfahren zum Einhüllen einzelner Heilmitteltabletten (11) von im wesentlichen einheitlicher
Größe und Gestalt in einen Überzug (12) aus einem zur Einnahme geeigneten Polymer,
bei welchem zwei vorgeformte Filme (36, 37) des Polymers zur Annäherung aneinander
gebracht werden, indem sie um Abschnitte der Umfänge der jeweiligen Formen eines Paars
von ähnlichen, zylindrischen, örtlich ausgenommenen (108) Rotationsformen (38, 39)
gewickelt werden, wobei die Formen an einer horizontalen Berührungslinie, wo die Filme
sich abwärts bewegen, genau passen, bei welchem die Tabletten an der Berührungsstelle
einzeln zwischen die Filme eingeführt werden, wo die Filme von den Formen um die Tabletten
herum angebracht und zusammengeschweißt und entlang umgebender Linien (15) um und
nahe angrenzend an die Tabletten abgetrennt werden, und gekennzeichnet durch Herstellen
wüschenswerter Bedingungen der Filmformbarkeit, Spannung und Haftung der Filme an
den Tabletten und aneinander in den Filmen, wenn sie über den Formausnehmungen angeordnet
sind, und Darbieten der Tabletten einzeln zum Kontakt mit den sich bewegenden Filmen,
die der Berührungsstelle benachbart sind, die mit den Formausnehmungen ausgerichtet
ist, so daß die Filme sich ungehindert seitlich um den Gegenstand herum verformen
können, so daß die Tablette durch Bewegung der Filme in nicht getakteter, selbst abmessender
Weise ergriffen und in die Berührungsstelle in der Formausnehmung gezogen wird.
2. Verfahren nach Anspruch 1, bei dem die Tabletten (11) in einem Stapel angeordnet sind,
bei welchem die unterste Tablette im Stapel mit wenigstens einem der Filme (36, 37)
in Kontakt kommt.
3. Verfahren nach Anspruch 2, bei dem die Tabletten (11) in die Berührungsstelle eingeführt
werden, indem der Stapel an einem Ende in Kontakt mit wenigstens einem der zusammenlaufenden,
sich bewegenden Filme der Berührungsstelle benachbart angeordnet wird, so daß die
Endtablette des Stapels im Kontakt mit dem sich bewegenden Film dadurch ergriffen
und in die Berührungsstelle gezogen wird.
4. Verfahren nach Anspruch 3, bei dem die Endtablette des Stapels mit dem sich bewegenden
Film durch Schwerkraft in Berührung kommt.
5. Verfahren nach einem der Ansprüche 2 bis 4, bei dem jede Tablette (11) im Stapel in
einer gewüschten Beziehung zur Berührungslinie ausgerichtet ist.
6. Verfahren nach einem der Ansprüche 2 bis 5, bei dem die Anzahl der Tabletten (11)
im Stapel innerhalb eines ausgewählten Bereichs gehalten wird.
7. Verfahren nach einem der vorhergehenden Ansprüche, bei dem die Tabletten (11) den
Filmen (36, 37) als eine Säule von Tabletten mit ausgewählter Höhe in einem vertikalen
Durchgang (92) zugeführt werden, der sich an einer Stelle zwischen korrespondierenden
Formausnehmungen (108) zur Berührungsstelle öffnet, wobei sich jede Tablette in der
Säule ungehindert längs des Durchgangs unter der Vorbelastung durch die Schwerkraft
und das Gewicht anderer Tabletten über ihr in der Säule bewegen kann, und durch Auswählen
der Dicke, Formulierung, Temperatur und Spannung des Films und der Säulenhöhe in Koordination
miteinander, so daß sich die Tabletten aus dem Durchgang zu im wesentlichen gleichzeitigem
Kontakt mit den Filmen synchron mit der Bewegung korrespondierender, gegenüberliegender
Formausnehmungen in Ausrichtung miteinander in Reaktion auf die Rotation der Formen
verteilen.
8. Verfahren nach einem der vorhergehenden Ansprüche, bei dem das Polymer auf Gelatine
basiert und Gelatine und einen Weichmacher umfaßt, der in einem Gewichtsverhältnis
Gelatine zu Weichmacher im Bereich von etwa 3:1 bis etwa 15:1 vorliegt.
9. Verfahren nach einem der vorhergehenden Ansprüche, bei dem das Polymer Gelatine im
Bereich von etwa 40 bis etwa 60 Gew.-%, einen Weichmacher im Bereich von etwa 5 bis
etwa 12 Gew.-% umfaßt, wobei der Rest Wasser und Pigmente und Farbstoffe nach Wunsch
umfaßt.
10. Verfahren nach Anspruch 1 zum Umhüllen eines Gegenstandsvorformlings (11) mit einem
im wesentlichen verfestigten Polymer, bei dem wenigstens zwei Lagen aus im wesentlichen
verfestigtem Polymer (36, 37) zusammengezogen werden, um eine Berührungsstelle zwischen
den zusammenlaufenden Lagen zu bilden, wobei das Verfahren die Schritte umfaßt: (a)
Anordnen eines Stapels aus vollständigen Gegenstandsvorformlingen an einem Ende in
Kontakt mit wenigstens einer der zusammenlaufenden Lagen der Berührungsstelle benachbart,
so daß der Endvorformling des Stapels, der mit der Lage in Kontakt steht, von wenigstens
einer der zusammenlaufenden Lagen ergriffen und in die Berührungsstelle gezogen wird,
und (b) Verschweißen der beiden zusammenlaufenden Polymerlagen um den ergriffenen
und gezogenen Vorformling herum, um den Vorformling wenigstens teilweise in die Lagen
einzuhüllen.
11. Vorrichtung, die zum Umhüllen einzelner Heilmitteltabletten (11) von ausgewählter
Größe und Gestalt durch einzelnes Einführen der Tabletten zwischen zwei Filme (36,
37) aus einem zur Einnahme geeigneten Polymer geeignet ist, welche sich längs jeweiliger
Wege bewegen, die an einer Berührungsstelle zwischen einem Paar zusammenpassender,
synchron angetriebener, zylindrischer Rotationsformen (38, 39) zusammenlaufen, um
Abschnitte derer herum die jeweiligen Filme über die Formoberflächen gewickelt sind,
in deren Umfang eine jeweilige Linie aus mit Abstand voneinander angeordneten Ausnehmungen
(108) ausgebildet sind, von denen jede mit einer ähnlichen Ausnehmung in der anderen
Form zusammenarbeiten kann, um an der Berührungsstelle einen Hohlraum zu bilden, der
so bemessen ist, daß er eine Tablette (11) lose darin aufnimmt, wobei die Formen auch
an der Berührungsstelle zusammenwirken, um die Filme um jede Tablette herum entlang
einer Linie (15) um die Tablette herum und ihr nahe benachbart miteinander zu verschweißen
und die Filme im wesentlichen entlang jener Linie abzutrennen, und dadurch gekennzeichnet,
daß eine Einrichtung (52, 57, 58) zur Vorbehandlung der Filme mit den Filmwegen zusammenarbeitet,
um bei den Filmen, wenn sie über den Formausnehmungen angeordnet sind, vorbestimmte
Bedingungen der Verformbarkeit, Spannung und Haftung der Filme an den Tabletten oder
aneinander zu erzeugen und durch einen nicht getakteten, selbst abmessenden Tablettenspender
(56, 91, 92), der wie im Verfahren nach Anspruch 1 definiert bedienbar ist und der
sich zwischen den Formen (38, 39) im wesentlichen an der Berührungsstelle befindet,
um Tabletten einzeln zum im wesentlichen gleichzeitigen Kontakt mit den Filmen (36,
37) zur Aufnahme und zum Transport durch die Filme an Stellen der Filme darzubieten,
die über korrespondierenden Formausnehmungen (108) liegen, so daß jede dargebotene
Tablette sich mit den Filmen vom Spender in einem Hohlraum zu und durch die Berührungsstelle
bewegt und die Filme verformt und im Hohlraum um die Tablette herum zum einhüllenden
Eingreifen zwischen den Filmen gedehnt werden.
12. Vorrichtung nach Anspruch 11, bei der jede Tablette (11) wenigstens eine Symmetrieebene
(16, 161) aufweist, und bei der der Spender (56, 91, 92) und die Formen (38, 39) zusammenarbeitend
koordiniert sind, um zu bewirken, daß die Schweißlinie (15) der Filme um eine Tablette
herum im wesentlichen in einer jener Ebenen liegt.
13. Vorrichtung nach Anspruch 11 oder Anspruch 12, bei der eine Paßlinie zwischen den
Formen im wesentlichen horizontal ist und der Spender (56, 91, 92) einen im wesentlichen
vertikalen Durchgang (92) beinhaltet, durch den sich die Tabletten bewegen können
und der sein unteres Ende zur Formpaßlinie hin unmittelbar oberhalb der Paßlinie öffnet,
wobei der Durchgang seinem unterem Ende benachbart ausreichend lang ist, damit eine
Vielzahl von Tabletten im Durchgang in einer Säule angeordnet werden können, deren
unteres Ende sich am unteren Ende des Durchgangs befindet.
14. Vorrichtung nach Anspruch 13, bei der jede Tablette (11) in der Säule im Durchgang
(92) von der Tablette unter ihr getragen wird und die unterste Tablette in der Säule
sich ungehindert durch das untere Ende des Durchgangs in Kontakt mit den zusammenlaufenden
Filmen (36, 37) erstrecken kann.
15. Vorrichtung nach einem der Ansprüche 11 bis 14, bei der der Spender (56, 91, 92) unter
anderem für ausgewählte Eigenschaften der Tabletten (11), einschließlich ihrer Masse
und der Anzahl der in einer Säule im Durchgang (92) gestapelten Tabletten empfindlich
ist.
16. Vorrichtung nach einem der Ansprüche 11 bis 15, bei der der Spender (56, 91, 92) den
Zwischenraum zwischen benachbarten Ausnehmungen (108) längs der jeweiligen um die
Formen (38, 39) in Umfangsrichtung verlaufenden Linien beinhaltet.
17. Vorrichtung nach einem der Ansprüche 11 bis 16, bei der der Spender (56, 91, 92) so
arbeitet, daß er die Tabletten (11) in Kontakt mit den Filmen (36, 37) darbietet,
wobei die ausgewählte Symmetrieebene (16, 161) jeder Tablette im wesentlichen mit einer Ebene (54) zusammenfällt, auf der der Spender
zentriert ist, wodurch die Filme (36, 37) sich an einer Nahtlinie (15) zwischen den
Filmen im wesentlichen in der ausgewählten Symmetrieebene der Tablette verbinden.
18. Gegenstand, wie zum Beispiel eine Tablette, der durch das Verfahren nach einem der
Ansprüche 1 bis 10 hergestellt wurde, der zwischen zwei Filmen aus im wesentlichen
verfestigtem Polymer (z.B. einem zur Einnahme geeigneten Polymer) eingehüllt ist,
die entlang einer die Tablette umgebenden Linie verschweißt sind und an ihr enden
und an der Tablette haften, wobei die Filme aus einem nicht verformten Zustand von
entgegengesetzten Seiten der Tablette in Kontakt miteinander entlang der Linie um
die Tablette herum gedehnt sind.
19. Zusammensetzung, die zu einem Film gießbar ist, der speziell zur Verwendung beim Verfahren
nach einem der Ansprüche 1 bis 10 oder in einer Vorrichtung nach einem der Ansprüche
11 bis 17 angepaßt ist, wobei der Film fähig ist, um eine Heilmitteltablette herum
verformt zu werden und sich mit einem zweiten Film aus einer ähnlichen Zusammensetzung
zu verbinden, wobei die Zusammensetzung einen Weichmacher, eine Basisverbindung und
ein Lösungsmittel umfaßt, das mit dem Weichmacher und der Basisverbindung kompatibel
ist, wobei die Basisverbindung aus Gelatinen, modifizierten Gelatinen, Stärken, modifizierten
Stärken, Alginaten, Acrylaten, Polyvinylpyrolidin, Polyvinylalkohol, Cellulosederivaten,
sowohl Estern als auch Ethern, und Polysiloxanen ausgewählt ist.
1. Un procédé pour enrober des comprimés de médicament individuels (11) de taille et
de forme sensiblement uniformes dans une couche (12) d'un polymère pouvant être ingéré,
dans lequel deux films préformés (36, 37) du polymère sont entraînés pour avancer
en convergeant l'un avec l'autre en étant enroulés respectivement autour de portions
des circonférences de deux matrices rotatives (38, 39) similaires, cylindriques, présentant
des évidements locaux (108), les matrices venant en coïncidence au niveau d'une ligne
de pincement horizontale où les films descendent, les comprimés étant introduits individuellement
entre les films au niveau du pincement où les films sont appliqués autour des comprimés
par les matrices et sont soudés entre eux et découpés le long de lignes d'encerclement
(15) entourant les comprimés et étroitement contiguës à ceux-ci, et caractérisé par
l'établissement, dans les films tels que disposés sur les évidements des matrices,
de conditions désirées d'aptitude à la déformation des films, de tension des films
et d'adhésivité des films aux comprimés et entre eux, et par la présentation des comprimés
pour les faire venir individuellement en contact avec les films qui avancent, près
du pincement, en alignement avec lesdits évidements des matrices, en sorte que les
films soient libres de se déformer latéralement autour de l'article, de telle façon
que le comprimé soit saisi et attiré dans le pincement et dans l'évidement de matrice
par les films qui avancent, d'une manière auto-régulée non chronométrée.
2. Le procédé de la revendication 1, dans lequel les comprimés (11) sont arrangés en
une pile dans laquelle le comprimé du bas de la pile entre en contact avec au moins
l'un des films (36, 37).
3. Le procédé de la revendication 2, dans lequel les comprimés (11) sont introduits dans
le pincement en disposant la pile en contact à une extrémité avec au moins l'un des
films qui avancent en convergeant, en position adjacente au pincement, de sorte que
le dernier comprimé de la pile en contact avec le film qui avance soit saisi et attiré
dans le pincement par celui-ci.
4. Le procédé de la revendication 3, dans lequel le dernier comprimé de la pile est amené
par gravité en contact avec le film qui avance.
5. Le procédé de l'une quelconque des revendications 2 à 4, dans lequel chaque comprimé
(11) est aligné dans la pile en une relation souhaitée par rapport à la ligne de pincement.
6. Le procédé de l'une quelconque des revendications 2 à 5, dans lequel le nombre de
comprimés (11) dans la pile est maintenu dans un intervalle choisi.
7. Le procédé de l'une quelconque des revendications précédentes, dans lequel les comprimés
(11) sont apportés aux films (36, 37) sous forme d'une colonne de comprimés de hauteur
choisie dans un passage vertical (92) débouchant dans le pincement en une position
située entre des évidements de matrices correspondants (108), chaque comprimé de la
colonne étant libre de se déplacer le long du passage sous l'action de la gravité
et du poids des autres comprimés qui le surmontent dans la colonne, et en choisissant
l'épaisseur, la formulation, la température et la tension des films et la hauteur
de la colonne en coordination entre elles de sorte que les comprimés se distribuent
d'eux-mêmes à partir du passage pour entrer sensiblement simultanément en contact
avec les films en synchronisme avec le mouvement des évidements opposés correspondants
des matrices alignés entre eux, sous l'effet de la rotation des matrices.
8. Le procédé de l'une quelconque des revendications précédentes, dans lequel le polymère
est à base de gélatine et comprend de la gélatine et un plastifiant présents en un
rapport pondéral de la gélatine au plastifiant compris dans l'intervalle d'environ
3:1 à environ 15:1.
9. Le procédé de l'une quelconque des revendications précédentes, dans lequel le polymère
comprend de la gélatine en une proportion comprise dans l'intervalle d'environ 40
pour cent à environ 60 pour cent en poids, un plastifiant en une proportion comprise
dans l'intervalle d'environ 5 pour cent à environ 12 pour cent en poids, le reste
étant de l'eau et des pigments et colorants tels qu'ils peuvent être souhaités.
10. Le procédé de la revendication 1 pour enrober une préforme d'article (11) avec un
polymère sensiblement solidifié, dans lequel au moins deux feuilles d'un polymère
sensiblement solidifié (36, 37) sont tirées ensemble pour former un pincement entre
les feuilles convergentes, le procédé comprenant les étapes suivantes : (a) placer
une pile de préformes d'article complètes en contact à une extrémité avec au moins
l'une des feuilles convergentes, au voisinage immédiat du pincement, de telle manière
que la préforme se trouvant à l'extrémité de la pile en contact avec la feuille soit
saisie et attirée dans le pincement par au moins l'une des feuilles convergentes,
et (b) souder les deux feuilles de polymère convergentes autour de la préforme saisie
et attirée pour enrober au moins partiellement la préforme dans les feuilles.
11. Appareil convenant pour enrober des comprimés de médicament individuels (11) de taille
et de forme prédéterminées, en introduisant les comprimés individuellement entre deux
films (36, 37) d'un polymère pouvant être ingéré qui avancent suivant des chemins
respectifs qui convergent au niveau d'un pincement entre deux matrices cylindriques
appariées rotatives entraînées de façon synchrone (38, 39), les films respectifs s'enroulant
autour de portions de celles-ci en passant sur les surfaces des matrices dans la circonférence
desquelles sont formées des rangées respectives d'évidements espacés (108) dont chacun
coopère avec un évidement similaire de l'autre matrice pour former au niveau du pincement
une cavité dimensionnée pour recevoir un comprimé (11) avec un ajustement lâche, les
matrices agissant également de concert au niveau du pincement pour souder les films
entre eux autour de chaque comprimé le long d'une ligne (15) entourant le comprimé
et étroitement contiguë à celui-ci et pour découper les films essentiellement le long
de cette ligne, et caractérisé en ce que des moyens de conditionnement de films (52,
57, 58) coopèrent avec les chemins des films pour établir dans les films, tels que
disposes sur les évidements des matrices, des conditions prédéterminées d'aptitude
à la déformation des films, de tension des films et d'adhésivité des films aux comprimés
et entre eux, et par un distributeur de comprimés autorégulé non chronométré (56,
91, 92) qui peut fonctionner comme défini dans le procédé de la revendication 1 et
qui est situé entre les matrices (38, 39) sensiblement au niveau du pincement pour
présenter les comprimés individuellement, de sorte qu'ils entrent en contact avec
les films (36, 37) essentiellement simultanément pour être pris et transportés par
les films en des emplacements des films qui recouvrent des évidements de matrice correspondants
(108), de telle manière que chaque comprimé présenté avance avec les films dans une
cavité en passant du distributeur au pincement et en franchissant celle-ci et que
les films soient déformés et étirés dans la cavité autour du comprimé entrant en prise
d'enrobage entre les films.
12. L'appareil de la revendication 11, dans lequel chaque comprimé (11) présente au moins
un plan de symétrie (16, 16') et dans lequel le distributeur (56, 91, 92) et les matrices
(38, 39) sont coordonnés entre eux pour faire en sorte que la ligne (15) de soudure
des films autour d'un comprimé se situe essentiellement dans l'un de ces plans.
13. L'appareil de la revendication 11 ou de la revendication 12, dans lequel une ligne
de coïncidence entre les matrices est sensiblement horizontale et le distributeur
(56, 91, 92) comprend un passage sensiblement vertical (92) dans lequel les comprimés
peuvent se déplacer et qui débouche à son extrémité inférieure vers la ligne de coïncidence
des matrices juste au-dessus de la ligne de coïncidence, le passage étant suffisamment
long à partir de son extrémité inférieure pour que plusieurs comprimés puissent être
disposés dans le passage sous forme d'une colonne dont l'extrémité inférieure se situe
au niveau de l'extrémité inférieure du passage.
14. L'appareil de la revendications 13, dans lequel chaque comprimé (11) de la colonne
formée dans le passage (92) est supporté par le comprimé situé sous lui et le comprimé
le plus bas de la colonne est libre de dépasser par l'extrémité inférieure du passage
pour entrer en contact avec les films convergents (36, 37).
15. L'appareil de l'une quelconque des revendications 11 à 14, dans lequel le distributeur
(56, 91, 92) est sensible, entre autres, à des caractéristiques choisies des comprimés
(11), y compris leur masse et le nombre de comprimés empilés dans une colonne formée
dans le passage (92).
16. L'appareil de l'une quelconque des revendications 11 à 15, dans lequel le distributeur
(56, 91, 92) comporte un espacement entre des évidements (108) adjacents le long des
lignes de circonférence respectives des matrices (38, 39).
17. L'appareil de l'une quelconque des revendications 11 à 16, dans lequel le distributeur
(56, 91, 92) opère de façon à présenter les comprimés (11) en les amenant au contact
des films (36, 37) de sorte que le plan de symétrie choisi (16, 16') de chaque comprimé
coïncide sensiblement avec un plan (54) sur lequel le distributeur est centré, si
bien que les films (36, 37) se joignent au niveau d'une ligne de soudure (15) entre
les films qui se trouve sensiblement dans le plan de symétrie choisi du comprimé.
18. Un article, par exemple un comprimé, produit par le procédé de l'une quelconque des
revendications 1 à 10, enrobé entre deux films de polymère sensiblement solidifié
(par exemple un polymère pouvant être ingéré) qui sont soudés ensemble le long d'une
ligne entourant le comprimé et se terminent à cette ligne et qui adhèrent au comprimé,
les films étant étirés, à partir d'un état non déformé, autour du comprimé depuis
les faces opposées du comprimé jusqu'à leur zone de contact mutuel le long de la ligne.
19. Une composition moulable en un film spécifiquement adapté à une utilisation dans le
procédé de l'une quelconque des revendications 1 à 10 ou dans l'appareil de l'une
quelconque des revendications 11 à 17, le film étant capable d'être déformé autour
d'un comprimé de médicament et de se lier à un second film de composition similaire,
la composition comprenant un plastifiant, un composé de base et un solvant compatible
avec le plastifiant et le composé de base, le composé de base étant choisi parmi les
gélatines, les gélatines modifiées, les amidons, les amidons modifiés, les alginates,
les acrylates, la polyvinylpyrrolidone, le poly(alcool vinylique) , les dérivés cellulosiques,
tant les esters que les éthers, et les polysiloxanes.